Lecture on Short Stories from Quantum Information Theory Prof. Michael M. Wolf (TUM) The talk aims at providing a taste of Quantum Information Theory exemplified through two problems from different branches of the field. In the first part we will encounter quantum correlations that are arbitrarily stronger than their classical counterparts. In physics this is related to the foundations of quantum theory, in mathematics to Grothendieck type inequalities within operator space theory, and in theoretical computer science to the reduction of communication complexity. The latter perspective suggests how - in the distant future - the scheduling of the colloquium might be made more efficient. The second part will shed new light on the energy gap problem from condensed matter theory. Despite considerable effort and interest, there is basically neither a proof technique nor a numerical method known for solving this type of problem. We will argue that the roots of this difficulty may be deeper than expected by showing that there are cases for which there cannot be a proof (in the sense of Gödel) or an algorithm (in the sense of Turing).